Tooth And Guiding Means Therefor For Excavating Equipment

Abstract

A tool, especially for earth-working implement, in which the tool which has a tooth section and a shank section has its shank section clamped within a tongue-equipped sleeve by screwbolt means extending through said tongue section and the adjacent shank section.

Description

The present invention relates to a tooth and guiding means therefor for excavating equipment and in particular relates to a sleeve for the cutting edges of digging vessels of power-driven equipment for digging and excavating purposes.

With stripping shovels or buckets, the cutting force is produced through the intervention of a cable line substantially in one direction upon the cutting knife. In this connection, fork-shaped teeth with U-shaped legs are known which are slipped over the bucket front and which additionally clamp the tooth to the bucket front by means of a screw passed through the ends of said legs. This advantage is affected by the drawback that such teeth with two legs are expensive because the teeth are subjected to considerable wear and therefore have frequently to be exchanged.

With another heretofore known arrangement, sleeves are employed which are welded into the bucket front of the digging vessel. The teeth which are provided with one leg only are introduced into the sleeves and are secured against withdrawal by means of a pin passed through the sleeve and the tooth. However, when the load becomes too high, the holding pin frequently is no longer able to transmit the pulling forces and shears off so that the tooth is pulled out of the sleeve and passes between the rocks and together with said rocks gets into the jaw crusher where it causes considerable damage.

It is, therefore, an object of the present invention to provide an arrangement of the type mentioned above in which the tooth will be shaped so that it can be produced at lower cost while permitting at the same time to take advantage of the clamping effect for a better connection so that the drawbacks of heretofore known similar arrangements will be avoided.

This object has been realized according to the present invention by preventing the pulling out of the tooth from the sleeve or socket by a clamping effect brought about by means of a screw and a tongue in the sleeve at the inner end of the shank of the tooth. According to a specific embodiment of the present invention that end of the sleeve which is remote from the cutting edge and that side of the sleeve which faces the back of the digging vessel are provided with a tongue formed by a slot and producing the clamping effect and are furthermore provided with two bores for receiving a screw.

By means of the clamping effect produced in the sleeve, which clamping effect may be further increased by a conical design of that end of the leg of the tooth which faces away from the cutting edge and by a corresponding design of the sleeve, the tooth will be firmly held in the sleeve even at unusually high loads. This advantage has been realized without sacrificing the one leg design of the tooth which, as mentioned above, is more favorable as to wear and frequent exchange.

While the above-mentioned sleeve type according to the invention is intended primarily for heavy duty operations, teeth and sleeves of the above-mentioned type according to the present invention are unnecessarily expensive when used only or primarily for loading operations or for working in light soil where the primary object is the loosening of the soil.

It is, therefore, a further object of this invention to provide an arrangement which while retaining a firm and strong clamping effect of the holding means for the teeth will make it possible to provide a simplified wedging engagement of tooth and guiding means therefor for excavating equipment with which the loading bucket will have a smooth surface at the bottom.

This object has been realized by making the sleeve or socket forming the guiding means for the tooth of one single piece and of a U-shaped cross secton while that end of the sleeve which is remote from the cutting edge has its closed side provided with a slot to produce a clamping effect, said sleeve furthermore being provided with a bore for receiving a fastening screw. According to this embodiment, one longitudinal wall of the sleeve is formed by the bottom plate of the loading bucket so that the sleeve will not only be simple in manufacture but may also have a completely smooth bottom side.

The invention is illustrated by way of example in the accompanying drawings, in which:

FIG. 1 is a longitudinal section through a tooth and the guiding sleeve or socket therefor according to the invention.

FIG. 2 is a side view of the sleeve as seen in the direction of the arrow A of FIG. 1 and shows the tongue for producing a clamping effect of the sleeve on the shank or the leg of the tooth.

FIG. 3 is a section through a portion of the rear end of the tooth and shows a sleeve which is slightly modified over that of FIGS. 1 and 2.

FIG. 4 is a partial section through a tooth and the holding means therefor and differs from that of FIG. 1 primarily by additional friction discs.

FIG. 5 illustrates a longitudinal section through a modified arrangement according to the invention and, more specifically, shows a longitudinal section through a tooth with a sleeve connected to the bottom plate of the bucket.

FIG. 6 is a side view of FIG. 5 as seen in the direction of the arrow B of FIG. 5 but without the tooth.

FIG. 7 is a section taken along the line VII-VII of FIG. 6.

Referring now to the drawings in detail, the guiding means 1 for the tooth as illustrated in FIG. 1 are composed of two sections 1a and 1b which, as shown in FIG. 1, are welded together at 2 to form the sleeve or socket. That end of sleeve or socket 1 which is adjacent the tooth 3 has its inner surface designed so as to form a steep cone 4 for receiving the teeth 3 in a wedging engagement under force exerted on the teeth during operation. The closed end of sleeve or socket 1 receives that portion of the tooth shank which is provided with planar straight surfaces 5. This portion of sleeve 1 is provided with a slot 6 as shown in FIG. 2 so that by means of said slot 6 a resilient tongue 7 is formed. A screw bolt 8 is passed through bores 9, 9a in tongue 7 and socket 1 and through a passage 15 in the leg shank 1c of tooth 3 thereby making it possible, when tightening the screwbolt 8, to firmly clamp the tooth shank 1binto the socket 1.

According to another embodiment of that end of tooth 3 which faces away from the cutting edge and of sleeve 1, that portion of tooth 3 which is remote from the cutting edge is provided with a steep cone 10 which corresponds to the conical portion 11 of the sleeve as shown in FIG. 3. The clamping effect of tongue 7 may be improved by friction linings 8a which may be mounted between the leg or shank of tooth 3 and the inner walls of sleeve 1 in recesses 1d provided at the exit openings of the axially aligned opposite bores 9. Such an arrangement is clearly shown in FIG. 4.

It will be appreciated that the clamping of the tooth may also be brought about by means of tongues formed by slots at the longitudinal sides or the bottom side of the sleeve. Furthermore, the steep cone 4 may also be replaced by a cylindrical bore.

Referring now to the embodiment of FIGS. 5 to 7, it will be noted that the socket 11 for guiding the tooth is formed by a welding seam 12 by means of which the sleeve 11 is welded to the bottom plate of a loading shovel not shown in the drawing. By means of a screwbolt 14 which is passed through bores 15 and 16 in sleeve 11 and the bottom plate and through a passage 18 provided in the leg 17b of the tooth 17, the tooth 17 is secured against dropping out of socket. When tightening the screw 14 by means of the nut 19, the tongue 21 formed by the slot 20 is pressed against the shank or leg 17b of tooth 17 so that the latter is clamped against the bottom plate 13. The inclined surfaces at 22 wedge the tooth into the socket under the forces of the digging operation.

It is, of course, to be understood that the tooth and the sleeve according to the present invention are not limited to dredges but can be employed in connection with all other earth-moving and excavating equipment. Moreover, the cone 22 may also be replaced by parallel-guiding means. The tongues, instead of being provided on one of the three longitudinal sides of the sleeve, may also be provided in the bottom plate of the shovel or bucket. Furthermore, the sleeves may be welded to the bottom side of the bottom plate.

It is furthermore to be understood that the present invention is not limited to the particular constructions shown in the drawings but also comprises numerous modifications, the scope of the invention being determined by the appended claims.

Claims

I claim:

1. In digging equipment in which the cutting edge of a digging member is provided with digging teeth, said digging member comprising a socket extending longitudinally inwardly form the edge of the digging member, and a tooth having a digging end outwardly of said socket and a shank extending longitudinally into said socket from said digging end, the outer portion of said shank and the outer end of said socket having engaging complementary inclined surfaces converging longitudinally inwardly from the outer end of said socket with the transverse dimension across said surfaces being greatest on said shank, so that said inclined surfaces on said shank and socket may be forced into a wedging engagement, the inner end of said shank and of said socket each having a pair of longitudinal substantially parallel planar surfaces with the planar surfaces on said shank fitting between and substantially parallel to the longitudinal surfaces of said socket, said socket and said shank having aligned apertures extending through said longitudinal surfaces, the wall of one of said longitudinal planar surfaces on said socket having slits on opposite sides of its aperture to provide a resilient portion about said aperture, and a clamping bolt extending through said apertures to clamp said end of said shank between said surfaces on said socket, certain of said apertures being sufficiently larger than said bolt that said shank is provided with a limited amount of freedom to permit wedging of said shank and socket during use while the clamping action of the bolt and resilient wall portion prevents said tooth from being loosened in said socket.

2. In digging equipment according to claim 1, in which the slits on opposite sides of said aperture are connected across their ends on one side of said aperture to form a resilient tongue.

3. In digging equipment according to claim 1, in which each of the inclined surfaces on said socket and shank is a conical surface.

4. In digging equipment according to claim 1, in which friction disc members are positioned between the longitudinal surfaces on the inner ends of said socket and shank.

5. In digging equipment according to claim 1, in which a flat side of said digging member forms one side of said socket, said side having one of said inclined surfaces engaged by one of the complementary surfaces on said shank, said socket and shank also having complementary inclined engaging surfaces on their opposite sides.